Oral health is a prerequisite for a good chewing function, which may have an impact on food choices and nutritional well-being. OBJECTIVE: This study was designed to evaluate the relationship between oral health status and nutritional status in the elderly. MATERIAL AND METHODS: In this cross-sectional study, 33 elderly people from the Group for the Elderly Interdisciplinary Geriatrics and Gerontology Program, at Fluminense Federal University, Niteroi, RJ, Brazil, completed a questionnaire to collect information on socioeconomic status, eating habits, physical activity and health habits, undertook a clinical oral examination, blood test, and anthropometric measurements, and were allocated into groups according to age. The oral health status was assessed using the index for decayed, missing and filled teeth (DMFT). The nutritional status was assessed using hemoglobin, hematocrit and albumin concentrations in blood, anthropometric values and the body mass index. RESULTS: Tooth loss was the biggest nuisance to the elderly subjects (57.6%), followed by the use of dentures (30.3%) and ill-fitting dentures (33.3%). 66.6% of patients had difficulty in chewing, and 54.5% reported this to be due to prostheses and 13.6% to the absence of teeth. A significant correlation was found between DMFT and the value of suprailiac skinfold thickness (rho=0.380, p=0.029). CONCLUSION: The results support the temporal association between tooth loss and detrimental changes in anthropometry, which could contribute to increased risk of developing chronic diseases.

Oral health is a prerequisite for a good chewing function, which may have an impact on food choice and nutritional well-being16,22. A variety of oral conditions can lead to an inadequate nutritional status, including tooth loss, pain and discomfort associated with caries, periodontal disease and ill-fitted dentures22. The absence of teeth in particular can affect the digestive capacity and nutritional status of the individual. Furthermore, the selection of food can be impaired due to the reduced masticatory capacity of the individual, leading to a restricted intake of fiber- and protein-containing foods21. The presence of natural teeth and well-fit dentures has been linked to an increased variety of foods and nutrient intake, which will contribute to the consumption of a diet rich in fiber11.

Maintaining an adequate nutritional status is important because an inadequate health status can lead to either underweight, which increases the risk of infections and mortality27, or possible overweight, which increases the risk of chronic diseases such as hypertension and diabetes12,25.

The relationship between oral health and nutritional health in the elderly is complex and controversial, and current understanding of it is limited21. The aim of this study was to evaluate the relationship between oral health status and nutritional status of non-institutionalized elderly individuals.

MATERIAL AND METHODS

This investigation was conducted from May to August 2009 by the Group for the Elderly Interdisciplinary Geriatrics and Gerontology Program of the Fluminense Federal University, RJ, Brazil. The study plan had been approved by the Ethics Committee of the University, in accordance with the World Medical Association's Declaration of Helsinki28 (2000). Thirty-three independent elderly subjects of both genders were studied from a total of 100 individuals, aged 60 years old or over, the cut-off point for the definition of "elderly" recommended by the World Health Organization (WHO)24 (1989). The subjects were previously informed of the aims of the study, and consent forms were explained, read and signed by all the participants. For illiterate or low-reading level subjects, consent was obtained through their legal representatives. Excluded from the study were those individuals that were not in good enough physical and/or mental condition to participate in the collection of data, for example: those confined to wheelchairs, amputees, or those with problems of understanding that would prevent the measurements used in the study from being taken. The sample was divided into two groups, the Young Senior Group (YSG), with age not exceeding 70 years, and the Elderly Senior Group (ESG), aged over 70 years.

The evaluation of oral health status included the identification of decayed, missing, and filled teeth, and the presence of prostheses. The oral examination was conducted in daylight according to biosecurity standards and the findings reported in an odontogram as recommended by the WHO26 (1997). The index of decayed, missing and filled teeth (DMFT) was used due to its recommendation by the WHO26 (1997) to measure and compare the experience of dental caries in populations. For comparison and analysis of results the cut-off values used were those obtained from the Oral Health Survey of 2003 for the elderly age group (65 to 74 years) carried out in the Southeast region of Brazil3. The mean DMFT for this region was 28.61±6.44 which meant that dental health was satisfactory, this being defined when DMFT <22.17, with dental health status considered poor when DMFT >22.173. By transforming the DMFT index in Decayed (D), Missing (M) and Filled (F) the cut-off point was the average found in the Southeast where oral health status had satisfactory values of D>0.60, M>27.05 and F=0.91, and oral health status was poor with D>0.60, M>27.05 and F>0.913. The Kappa test was used to lend a greater reliability to the data collected, and the value of k was =0.9129, with a p-value below 0.01%. The importance of this test is that it shows that the value of K was significantly different from zero and this association is classified as "excellent". Other data on the oral health status were obtained with direct questions about intake of types of food and perception of the quality of dental prostheses3.

To assess nutritional status anthropometric measurements such as weight, height, arm circumference (AC), triceps skinfold thickness (TST), subscapular skinfold thickness (SST), suprailiac skinfold thickness (SIT), and waist circumference (WC) were measured by a trained professional according to the techniques recommended by the WHO27 (1995) for adults and the elderly. Weight (kg) was measured with a Filizola® balance (São Paulo, SP, Brazil), with the patient wearing minimal clothing and barefoot. The height, in meters, was measured by a stadiometer attached to the balance. The Body Mass Index (BMI) was determined by the weight (kg) and height squared (m). The diagnosis of nutritional status according to BMI was classified according to criteria established by the WHO25 (2000), used for adults and elderly individuals, as normal weight (18.5 to 24.9 kg/m2), overweight (25-29.9 kg/m2), obesity class I (30-34.9 kg/m2), obesity class II (35-39.9 kg/m2) and obesity class III (>40 kg/m2). The AC was measured with the arm extended horizontally to the average level of the arm. The examiner was positioned to the side and passed the graduated, flexible and inelastic tape, with an accuracy of 0.1 cm, around the arm. The cut-off indicates as high values >29.9 mm for women and >30.7 mm for men6. All skinfolds were measured using the Lange skinfold caliper (Lange, Beta Technology Incorporated®, Santa Cruz, CA, USA), with constant pressure of 10 g/mm and an accuracy of 1 mm. The triceps skinfold thickness (TST) was measured in the upper arm 1 cm above the midpoint of a line joining the acromion to the olecranon. The cut-off values indicate as high those values >24.0 mm for women and >11.0 mm for males6. The SST was measured on the left side with the arm in front of the body. The fold is measured at the inferior angle of the scapula, separating the muscle tissue. The cut-off point indicates as high values >19.8 mm for females and >17.4 mm for males23. The suprailiac skinfold thickness (SIT) was obtained with the right arm slightly away from the body, moving a fold of skin and fat away from the mid-axillary line and the iliac crest, in the oblique direction10. The cut-off point indicates as high values >19.8 mm for females and >17.9 mm for males23. The bicipital skinfold thickness (BST) was measured by moving a fold of skin and fat over the biceps muscle in a vertical direction (midline)10. Values >11.8 mm for women and >6.4 mm for men are considered as high23. The WC was measured at the edge of the iliac crest, in centimeters, using a tape measure belt. The cut-off points established by the WHO25 (2000) both for adults and for the elderly were employed: men with WC between 94 and 101.9 cm and women with WC between 80.0 and 87.9 cm are classified as being overweight and at increased risk for complications associated with obesity, while men with WC>102.0 cm and women with WC>88.0 cm are classified as obese and presenting a much greater risk for metabolic complications associated with obesity. The percentage of body fat (%BF) was determined using the sum of skinfolds: TST, BST, SST, SIT13, with a cut-off percentage for women of greater than 33% and for men a percentage above 22%9.

The nutritional status was also evaluated through the analysis of albumin, hematocrit and hemoglobin. The level of albumin in blood was verified by a bromocresol green colorimetric method using the kit Bioclin® (Bioclin, Quibasa Química Básica Ltda, Belo Horizonte, MG, Brazil), with reference values from 3.5 to 5.5 g/dL (BIOSPECTRO®, SP 220). The hematocrit was measured by the capillary tube method, with reference values of 37% to 47% for women and 40% to 54% for men (MICROSPIN, Mod Spin 1000). A colorimetric method was employed to measure hemoglobin (BIOSPECTRO®, SP 220), with reference values of 11.5 g/ dL to 15.5 g/ dL for women and 12.5 g/dL to 17.5 g/dL for men (Bioclin®).

The data obtained were presented in descriptive form as mean, standard deviation and percentage. For comparison of continuous variables between the two groups, we used Student's t test for independent samples or the Mann-Whitney test. To examine the correlations between continuous variables we used Pearson's correlation test or Spearman's. For the correlations between variables, we used Fischer's exact test.

RESULTS

The elderly patients evaluated had an mean age of 71.7±5.35 years, and were divided into 2 groups: Young Senior Group (YSG), with 13 individuals (39.4%), and the Elderly Senior Group (ESG) with 20 (60.6%); 97% of subjects were female and 3% were male.

The average DMFT was calculated for both groups: YSG=20.60±6.17 and ESG=21.44±7.26. On closer examination of this index it was found that the means for decayed (0.75±1.84, p=0.274) and missing teeth (20.06±9.27, p=0.808) were higher in the ESG. The mean value for filled teeth found in the ESG (0.62±1.54, p=0.464) was lower than that found in the YSG. The average number of teeth in the mouth was higher in the YSG, although there were no statistically significant differences between the groups (Table 1).

The mean body mass index (BMI) of 30.17±5.38 kg/m2 for the YSG classified them as overweight, while the ESG was of normal weight, with an average BMI of 27.21±4.11 kg/m2. The AC and BST values were elevated in both groups, with average values of 31.64±4.66 cm and 14.55±7.96 mm, respectively. Of the indicators SST (19.26±6.15 mm) and SIT (19.62±9.85 mm) among individuals classified as overweight in the YSG, a significant difference was noted in the values of SST compared to the ESG (p=0.022). According to the WC of the YSG, calculated to be 97.93±14.08 cm, this group is classified as overweight and at increased risk for complications associated with obesity. Similarly, the percentage of body fat (% BF) was elevated in the YSG, with a mean of 37.70±5.95%. On this indicator the ESG also showed a raised value (34.64±6.15%). The biochemical indicators blood albumin, hematocrit and hemoglobin were within normal limits, with no differences between groups (Table 2).

The DMFT index was not significantly associated with the BMI (χ2=0.636, p=0.364), blood albumin (χ2=0.185, p=0.508), hematocrit (χ2=1.102; p=0.182) and hemoglobin (χ2=0.016, p=0.714). However, 81.8% of patients were overweight or obese; of these, 36.4% (n=12) had an unsatisfactory DMFT value (Table 3).

In the evaluation of the oral health status, considering the use of ill-fitting dentures (IFP), it was found that 54.5% of the subjects had an altered BMI (overweight or obesity), therefore without any statistical significance (Table 4).

In relation to prostheses that make it difficult to chew (PDC), 17 patients (51.5%) proved to be dissatisfied, and 13 (39.4%) had a change in their nutritional status (χ2=0.136, p=0.656). As for the patients who avoided foods (AF), 17 (51.5%) were among those who had altered oral health status (Table 4). In evaluating the consistency of the food, it was found that at least one third of the subjects prefer putty (n=12, 36.40%), soups (n=9, 27.30%), chopped (n=11, 33.30%), ground (n=11, 33.30%), crushed (n=12, 36.4%) or boiled (n=10, 30.3%) food. Biochemical indicators such as blood albumin, hematocrit and hemoglobin did not show any association with DMFT and its components decayed, missing and filled teeth (Table 3), IFD, PDC and AF (Table 4).

In the analysis of the BMI and the anthropometric and biochemical markers, a significant correlation was found between BMI and the variables AC (r=0.942, p<0.001), TST (r=0.740, p<0.001), BST (r=0.669, p<0.001), SST (r=0.847, p<0.001), SIT (r=0.828, p<0.001) and WC (r=0.868, p<0.001). The DMFT index was correlated significantly only with the variable suprailiac skinfold thickness (SIT) (rho=0.380, p=0.029) (Table 5).

DISCUSSION

In the present study, we found that changes in oral health can influence the diet, reflecting in the nutritional status of the individual22. Review of the literature has shown that patients who have marked loss of teeth may be prone to a decrease in the intake of foods with a heavy consistency, which are a major source of vitamins, minerals, fiber and protein19,21. However, it is important to note that there are several factors other than oral health status that influence food choice, such as personal preferences, available food sources and dietary habits, as well as psychosocial and economic factors19.

In relation to DMFT, the reference was to the southeast of the country, given that the subjects were residents of the state of Rio de Janeiro. In the sample studied it was found that both the YSG and ESG had DMFT values that were inferior to that observed in the survey SB Brazil for Southeast, which was 28.61±6.443. When stratifying the DMFT, the comparison of these averages with the average value observed in the Southeast showed that only YSG presented a lower value for decayed teeth. Regarding missing teeth, both the ESG and YSG had mean values below that of the region. It was found that in the YSG the number of filled teeth was not satisfactory. Although there was no significant difference in relation to filled teeth between the YSG and ESG, it was found that the number of healthy teeth in the mouth decreased with age. Similar findings were reported from a study involving elderly individuals aged between 65 and 74, the youngest of whom (65 to 69 years) had a greater number of teeth. On the other hand, the DMFT in that study was 26.2 and the missing component accounted for 20.7 teeth17, both values being higher than those found in the present study, where the DMFT of the sample was 20.19 and the missing component accounted for 19.65.

The reduced number of healthy teeth and the presence of filled teeth in the mouth can also contribute to the choice of foods. Considering complaints of difficulty in chewing from the use of dentures, either partial or complete, and the influence on food choice, our findings are similar to those that mentioned that users of dentures have a reduced ability to chew compared with those patients with at least 20 teeth in the dental arch15,21.

In agreement with the conclusions of Esfandiari, et al.5 (2009), the psychological condition of the elderly person should be considered when choosing the diet, which justifies the option of implants for use of the overdenture. Chewing ability is associated with not only oral health status but also the physical constitution of the elderly, since it may contribute to the regulation of the nutritional status in the elderly14.

In the present study, there was no significant difference between the groups in the values found for DMFT, BMI and albumin. In relation to BMI, Sadamori, Hayashi and Hamada18 (2008) reported no significant difference between users and nonusers of dentures. However, a difference was observed in the amount of albumin present in the blood of the two groups (94 elderly women, mean age 89.6±5.6), being lower for users of prostheses. According to Collins4 (2001), the monitoring of albumin levels can provide a measure of the long-term condition of the patient's protein levels.

In the analysis of hemoglobin and hematocrit, there was no statistically significant difference between the DMFT and BMI. However, it was observed that 36.4% of subjects did not have an ill-fitting prosthesis and had adequate hemoglobin (χ2=2.881, p=0.054). In relation to BMI, it was found that the mean indicated overweight in the YSG while in the ESG the value was normal. The difference between the groups on BMI values was similar to that found in a study which reported a lower BMI in older individuals2. The reason for the ESG having a mean value for BMI below that found in the YSG is probably the reduction in the number of teeth present and the reporting of dentures that cause discomfort, leading the research subjects to specific choices over foods19. Similarly, other authors have reported that edentulousness in the elderly, with an average age of 71 years, while not related to BMI was linked to a lower intake of nutrients, indicating that nutrient intake is associated with oral health status when defined by clinical indicators1. On the other hand, another study did find an association between poorer oral health status and obesity in elderly subjects aged between 60 and 90 years7.

Cutaneous skinfolds, although not the single most accurate form for assessing body fat percentage, are better indicators of the amount of body fat than the body mass index (BMI)8,27. When comparing DMFT with anthropometric indices, there was a positive and statistically significant correlation only with the indicator of central adiposity, the suprailiac skinfold thickness8.

In this study the indicators arm circumference and bicipital skinfold thickness (AC and BST) were altered in the YSG and ESG. Although the BMI value was 27.2 in the ESG, the SST and SIT indicators classified the subjects of YSG and ESG as overweight (19.26±6.15 mm, 19.62±9.85 mm respectively). Significant differences were found in SST values between the YSG and ESG. This difference suggests a trend of nutritional changes that may also be related to tooth loss and the use of removable dentures in the elderly senior. Other indicators such as waist circumference (WC), triceps skinfold thickness (TST), and body fat percentage (%BF) presented values that were not statistically significant compared with DMFT and BMI. Similar to the BMI, waist circumference (WC), with a mean value of 94.5±11.38 cm classified the sample as being overweight and at increased risk for complications associated with obesity, especially in the YSG27. However, it should be recalled that values of BMI used to identify overweight in the general adult population may lead to an overestimation in the number of overweight elderly. Similar problems appear to exist when assessing waist circumference values20.

Overall, the findings obtained and discussed in this work are relevant to ongoing research linking oral health and nutritional status in order to reach an optimal quality of life for the elderly.

CONCLUSION

According to the number of elderly participants in this pilot study, it may be concluded that the DMFT index was satisfactory in 60.7% of the patients. Tooth loss was the biggest concern of the elderly in accordance with the high percentage of ill-fitting dentures (45.5%) and prostheses that make it difficult to chew (51.5%). There was a significant correlation between DMFT and the thickness of the suprailiac skinfold (rho=0.380, p=0.029).